Under a bill introduced by School Board member Yolie Flores Aguilar, private operators could bid for control of 50 new campuses and hundreds of struggling ones.

Los Angeles Mayor Antonio Villaraigosa said Tuesday he will push the school district to allow outside operators to bid for control of hundreds of campuses, a move he described as the centerpiece of education reform for his second term.

The proposal drew the ire of the teachers union, which has strongly criticized the mayor's own school-improvement efforts at 10 schools, including Roosevelt High in Boyle Heights. Villaraigosa, in turn, called the union "the biggest defender of the status quo."

The mayor's goal, embodied in part in a proposal by Board of Education member Yolie Flores Aguilar, would let charter-school organizations, the mayor's nonprofit and other groups compete to run 50 new schools scheduled to open over the next four years. The school board is scheduled to take up that motion later this month.

Villaraigosa also wants to allow outside groups or the district to shut down and restaff hundreds of existing schools that have long been rated "failing" under federal accountability rules. Supt. Ramon C. Cortines and other officials have said that closing unsuccessful schools is a logical outgrowth of the Flores Aguilar plan.

"This is the most significant reform proposal that this school district has ever put forth because it is . . . far-reaching," Villaraigosa said in an interview. "We've got to reconstitute failing schools."

Flores Aguilar, who is traveling abroad, introduced her proposal in July; it was greeted by enthusiasm as well as intense opposition. At the time, the mayor agreed with those pushing for a delay on the matter, but insisted he supported it. Tuesday he removed any lingering doubt.

"This will not be easy," Villaraigosa said before about 50 community members at the Catholic Charities facility east of downtown. "When you go to the fights, they say: 'Ladies and Gentleman, let's rumble.' "

Critics include United Teachers Los Angeles and other employee unions.

"Yolie's proposal could lead to chaos in the education system in this city. It is not well thought out. Nor is it based upon data," UTLA president A.J. Duffy said, citing studies suggesting that charter schools perform no better than traditional schools.

Duffy also opposes closing down existing schools, calling the approach unproven. He also said the mayor has "terribly mismanaged" the schools already under his purview.

Villaraigosa said he's optimistic that pending test scores will demonstrate progress at his schools.

The event was organized by the Los Angeles Parents Union, which is affiliated with Green Dot Public Schools, a charter school operator. Last year, Green Dot took over the long-troubled Locke High in South Los Angeles.

Locke has made progress, demonstrating "that there is no excuse for failure," said Parents Union Director Ben Austin. But he said the goal is not to make all schools into charters, which would be "logistically, financially impossible."

Austin and Villaraigosa fielded questions before a receptive town hall audience assembled through Parents Union contacts. Locked outside were about 20 parents and teachers, many from Garfield High in East Los Angeles. Austin said he was worried about possible disruptions from competing forces vying to influence future reforms at Garfield.

Austin's group is attempting to win support for its Parent Revolution platform, which includes Flores Aguilar's resolution.

But UTLA and, separately, the Garfield staff also are assembling supporters. Another player is the community organization InnerCity Struggle, which has been closely allied with the mayor, but not the Parents Union.

The school district is exploring its already-authorized reform, through which large schools such as Garfield can be broken up into small ones. District officials gave up fully explaining this approach during a Monday night community meeting at nearby Griffith Middle School. That gathering of 400 devolved into a public comment session of district employees, parents and students who frequently denounced the district or the Parents Union.

Outside Tuesday's event, similar criticisms emerged.

"Garfield is already going in the right direction," parent Florentina Lopez said of the school's low but improving test scores. "Roosevelt High is the mayor's show. Why doesn't he do it there?"